In a process of manufacturing a semiconductor device, a substrate of a wafer or the like is coated with a chemical solution such as resist, so that a film is formed on the wafer. In such a resist coating process, as a method of uniformly coating a surface of the wafer with the resist, a spin coating method is used. The spin coating method is a coating method of dropping the resist on the wafer while rotating the wafer.
In such a spin coating method, in order to efficiently coat the wafer with a low consumed amount of the resist ejected from a nozzle, before the resist coating, a solvent is dropped from a center of the wafer. Therefore, a pre-wetting process of wetting the surface of the wafer in advance is performed.
However, in a case where the pre-wetting process is performed from the center position of the wafer, the content of the solvent occupied in the resist is different in a radial direction of the wafer. As a result, after an exposing process of forming a latent image of a pattern on the wafer and a developing process of forming a resist pattern are performed, dimensions and shape of the resist pattern is different in the radial direction of the wafer.